Dogs and wolves share 99.96% of their genetic material and are, by many measures, the same species. The dog is considered a domestic subspecies of the wolf, and the two can produce viable offspring (in fact, interbreeding between the two can probably account for some of the genetic similarity seen between dogs and modern wolves). So is your dog really just a tame wolf? Well, it turns out that there are some important differences between dogs and wolves that affect how they relate to us, and to others of their own kind.
Hunters vs. Scavengers
Dogs are social animals, but not pack animals in the sense that wolves are. A wolf pack is family unit, made up of one unrelated breeding pair, their offspring and other extended family members. Wolves have to take down large prey and must work closely with one another in order to hunt successfully. Contrary to popular notions of wolf packs as rigidly structured and highly competitive, social relations among pack members are generally peaceful, with pack hierarchy being maintained through play and repetitive ritualized behaviour, as well as genuine bonds of affection between pack members.
In their partnership with humans, dogs have given up the need to hunt large game. Dogs, when left to their own devices, typically live as scavengers around human settlements. These free-ranging dogs can still make and maintain social bonds with each other, but they are just as likely to be solitary. Rather than form packs, the dogs will separate themselves out, each scavenging in its own territory. If they do hunt, they hunt small prey that can be taken down by just one or two dogs. Unrelated dogs living together in close quarters (such as in the same household) can and do form hierarchies, but these hierarchies are based on competition and control of resources, such as food, rather than a cooperative pack structure.
The Critical Period
While dogs may have lost the ability to form strong social bonds with each other, they can form strong bonds with us, and this begins early in a dog’s life. Both dogs and wolves undergo a period in their development called a critical period: a one-month span early in their development, when puppies begin walking and exploring. They will retain familiarity with anything they come into contact with during this period, but after the four-week window closes, new sights, sounds & other stimuli elicit fear. Dog puppies begin their critical period at four weeks old, after their ears have opened and soon before their eyes open. Wolves, on the other hand, begin walking and exploring at two weeks, while they are still blind and deaf, relying primarily on their sense of smell. The timing of the dogs’ critical period could help explain why they can be tamed so easily; since they enter the critical period with more of their senses engaged, they are able to quickly adjust to sight and sound of humans. Dog puppies need as little as 90 minutes of contact with humans during their critical period in order to lose their fear of us. Wolf pups, on the other hand, need almost 24/7 contact with humans, starting at three weeks of age, in order to overcome their fear.
Man’s Best Friend
Even when wolves lose their fear of people, they seem unable to form close relationships with us in the same way that dogs do. In 2003, scientists at Eotvos University in Budapest hand-raised thirteen dogs and thirteen wolves from birth. All of the animals were hand-fed by their caregivers and were with them 24/7, even sleeping with them at night. Then, in the laboratory, the dogs and wolves were presented with food that was inaccessible to them; the animal had to rely on the experimenter. All it had to do was make eye contact with the experimenter to get some food. Both the dogs and the wolves tried to get food on their own at first, but by about the second minute, the dogs began looking towards the experimenter, whereas the wolves failed to make much eye contact at all. The wolves also never learned that eye contact was the key to getting the food. This suggests that even though wolves can lose their fear of humans, only dogs can see us as potential social partners.